This is the shocking moment a shaman ate raw buffalo meat at a ritual in northern Thailand.

The medium, dressed in all white, tucked into the farm animal's carcass during the annual Leang Dong or Forest Spirits Feast held in Chiang Mai.

Footage shows the woman, believed to be possessed, crouched in a field surrounded by worshippers as she devoured the sacrificial offering on June 10.

Moments later, apparently sated with the raw meat, she approached devotees with her back hunched to bestow blessings. She made bizarre faces as she acted as a vessel for forest spirits.

In another clip, the medium joined an elderly follower in a ritual dance, swaying to the rhythmic beat of drums.

The ancestral ceremony, which has been observed for more than 200 years, honours the forest guardian spirits Pu Sae and Ya Sae. A buffalo is traditionally slaughtered, with its meat and blood presented as offerings.

Once the spirits are believed to possess their respective mediums, they consume the offerings to symbolically receive the worshippers' respect and devotion.

After the ritual dances conclude, the spirits are said to depart from the mediums, marking the end of the ceremony.

However, this year's event sparked controversy among devotees. Many felt that the ritual lacked its usual sanctity, possibly due to a change in the primary medium.

Organisers said that the formal invitation rite to summon Pu Sae and Ya Sae had not yet been performed.

Worshippers speculated that the medium was possessed by a different spirit, leading to confusion among the crowd.

Eyewitnesses expressed concern over the woman's unusual behaviour, recalling that she smiled and wandered through the crowd repeatedly asking for photos.

The bizarre act left some attendees disillusioned, with several expressing a decline in faith following the ceremony.